2018/03/23 Dresden, Germany
Image: Michael Wagner/TU Dresden
Nature-based solutions can play an important role in improving the supply and quality of water and reducing the impact of natural disasters, according to the 2018 edition of the United Nations World Water Development Report. The study, which was launched this week around the world argues that reservoirs, irrigation canals, and water treatment plants are not the only water management instruments at our disposal.
On World Water Day (22 March), UNU-FLORES organised two launch events:
Dr Tamara Avellán and Dr Kai Schwärzel of UNU-FLORES contributed to this year’s World Water Development Report entitled “Nature-Based Solutions for Water”. In the report, they wrote about, among other things, the use of constructed or human-made wetlands as a low-technology alternative to treat wastewater. Wetlands can be introduced to an ecosystem as the collection and treatment point of wastewater. Not only can wetlands treat wastewater, but in such a system, nutrients that would otherwise be released into surface water or groundwater can be captured and used in agricultural lands instead. This offsets the need for artificial fertilisers and improves the quality of ecosystems to treat wastewater. Finally, the wetland plants which grow in this nutrient-rich environment can be harvested and used as an energy source.
Image: Michael Wagner/TU Dresden
In 1986, the State of Rajasthan in India experienced one of the worst droughts in its history. Over the following years, an NGO worked alongside local communities to set up water harvesting structures and regenerate soils and forests in the region. This led to a 30% increase in forest cover, groundwater levels rose by several metres, and cropland productivity improved.
These measures are good examples of the nature-based solutions (NBS) advocated by the latest edition of the World Water Development Report. It recognises water not as an isolated element, but as an integral part of a complex natural process that involves evaporation, precipitation, and the absorption of water through the soil. The presence and extent of vegetation cover across grasslands, wetlands, and forests influence the water cycle and can be the focus of actions to improve the quantity and quality of available water.
“Green solutions have always existed – we could learn much from historic water management and indigenous knowledge – but not always favoured or even seriously considered over traditional, human-built (so-called ‘grey’) infrastructure. The World Water Development Report 2018 illustrates that working with nature, rather than against it, would enhance the natural capital and support a resource efficient and competitive circular economy. Nature-based solutions can be cost-effective and provide environmental, social and economic benefits that are central to achieving the 2030 Agenda for Sustainable Development,” writes Gilbert Houngbo, Chair of UN-Water and President of the International Fund for Agricultural Development in the foreword of the report.
Nevertheless, the use of nature-based solutions remains marginal and almost all investments are still channelled to grey infrastructure projects. Yet, to satisfy the ever-growing demand for water, green infrastructure appears to be a promising solution complementing traditional approaches. The authors of the report, therefore, call for greater balance between the two, especially given that nature-based solutions are best aligned with the Sustainable Development Goals adopted by the United Nations in 2015.
Image: Michael Wagner/TU Dresden
Coordinated by the UN World Water Assessment Programme of UNESCO, the United Nations World Water Development Report is the fruit of collaboration between the 31 United Nations entities and 39 international partners that comprise UN-Water. Its publication coincides with World Water Day, celebrated every year on 22 March.
The World Water Development Report 2018 can be downloaded free–of–charge from the WWAP website. The Report is available in English, French, and Spanish. The Executive Summary is available for download in the six UN languages (Arabic, Chinese English, French, Russian, and Spanish) as well as in German, Italian, Hindi, and Portuguese. The Facts and Figures document is available for download in English, French, Italian, Portuguese, and Spanish. For any further information, the WWAP Secretariat remains available to reply to any query.